A proverb meaning that even a wrongdoer has some justification or reason—there is often at least a point in their side of the story.
事情を聞くと、彼にも言い分があった。盗人にも三分の理だ。
After hearing the circumstances, he had his reasons. Even a thief has a point.
裁判官は冷静に判断し、盗人にも三分の理があるかを探った。
The judge judged calmly and examined whether the wrongdoer had any valid reasons.
感情的に非難する前に、盗人にも三分の理があるかを考えよう。
Before blaming emotionally, consider whether the wrongdoer may have some justification.